Top most important tibco interview questions and answers by Experts:

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1.What are the modes of TIBCO BW Installations ?
• GUI mode
• Console mode
• Silent mode
2.If you have installed a particular version of TIBCO software e.g. TIBCO BW X.Y.Z, What are X, Y and Z number stands for?
Integration can be at different application layers:
• X:Patch
• Y:Major
• Z:Minor

3.What is the role of TRA?
TRA stands for TIBCO Runtime Agent.
The TRA has two main functions:
• Supplies an agent that is running in the background on each machine.
1. The agent is responsible for starting and stopping processes that run on a machine according to the deployment information.
2. The agent monitors the machine. That information is then visible via TIBCO Administrator.
• Supplies the run-time environment, that is, all shared libraries including third-party libraries.

4. What are the revision control system options available in TIBCO designer?
• File sharing
• VSS
• Perforce
• XML Canon
• ClearCase
• iPlanet
• CVS
• PVCS
5. What are the different modes of service invocation?
Services can be invoked in several ways.
• A one-way operation is executed once and does not wait for a response.
• A request-response operation is executed once and waits for one response. In a request-response service, communication flows in both directions. The complete interaction consists of two point-to-point messages—a request and a response. The interaction is only considered complete after the response has arrived.
• Publication (notification) means an operation sends information on an as-needed basis, potentially multiple times.
• Subscription means incoming information is processed on an as-needed basis, potentially multiple times.
6.What is vcrepo.dat?
TIBCO Designer creates a file named vcrepo.dat in the project root directory when you first save the project. This file is used to store properties such as display name, TIBCO Rendezvous encoding, and description. This file can be used for identification in place of the project root directory and can be used as the repository locator string (repoUrl).
7.What are the TIBCO BW activities that can participate in transactions?
Not all TIBCO BusinessWorks activities can participate in a transaction. Only the following types of activities have transactional capabilities:
• JDBC activities
• JMS activities
• ActiveEnterprise Adapter activities that use JMS transports
• EJB activities
• TIBCO iProcess BusinessWorks Connector activities

8.What are the different types of Transactions TIBCO provides?
TIBCO BusinessWorks offers a variety of types of transactions that can be used in different situations. You can use the type of transaction that suits the needs of your integration project. When you create a transaction group, you must specify the type of transaction. TIBCO BusinessWorks supports the following types of transactions:
• JDBC
• Java Transaction API (JTA) UserTransaction
• XA Transaction
9.What activities are supported in JTA Transaction?
The Java Transaction API (JTA) UserTransaction type allows:
• JDBC
• JMS
• ActiveEnterprise Adapter (using JMS transports)
• EJB activities
to participate in transactions.

10.What activities are supported in XA Transaction ?
The XA Transaction type allows:
• JDBC activities
• ActiveEnterprise Adapter activities that use the JMS transport
• JMS activities
to participate in transactions.
Note:For JMS activities and ActiveEnterprise Adapter activities, request/reply operations cannot participate in an XA transaction. Also, EJB activities cannot participate in an XA Transaction group.
11.What are the possible Error output’s of Read File activity?
Integration can be at different application layers:
• FileNotFoundException :Thrown when yhe file does not exist.
• UnsupportedEncodingException:Thrown when the text file’s encoding is not valid and the content of the file is read into process data.
• FileIOException :Thrown when an I/O exception occurred when trying to read the file.
12.What is the purpose of the inspector activity ?
The Inspector activity is used to write the output of any or all activities and process variables to a file and/or stdout. This is particularly useful when debugging process definitions and you wish to see the entire schema instead of mapping specific elements to the Write File activity.
13.What are the maximum/minimum of threads available for incoming HTTP ?
The maximum/minimum of threads available for incoming HTTP : 75/10
14. How can unauthorized users be prevented from triggering a process ?
Unauthorized users be prevented from triggering a process by giving ‘write’ access for the process engine to only selected users. Only users with ‘write’ access can do activities like deploying applications, starting/stopping process engines etc.
15.What are the mandatory configuration parameters for FTP Connection & FTP with firewall ?
The mandatory configuration parameters for FTP Connection
• FTP host
• Port
• Username & Password>
If Firewall is enabled in addition the proxy host and port are required.

16.how to design a process such that depending on number of records updated in a database, 3 different sub-processes may be called ?
Define 3 transitions from JDBC update with condition on the no of updates and call appropriate child processes.
17.How to use legacy .data file format with latest designer ?
Convert .dat file to multi file project using Administration tab while starting up Designer(Other one being Project tab) and then open the multi file project in the normal way.

18.What are the encodings supported by designer ?
Encodings supported by designer are
• ISO8859-1(Latin-1)
• UTF-8
19.What are the 4 main panels of the Designer window ?
The 4 main panels of the Designer window are
• Project panel
• Palette panel
• Design panel
• Configuration panel
20.How do you determine if there are broken references in the project?
Project -> Validate for deployment

21.Where are the Designer preferences stored ?
Designer preferences stored are stores in a file called ‘Designer <ver>.prefs’ in the user home directory.
22.Explain the process configuration parameters – Max Jobs, Flow Limit & Activation Limit ?
• Max Jobs :
Max Jobs specifies the number of process instances that are kept in memmory. Once this limit is reached newly created process instances (subject to flow limit) are paged out to disk.0 specifies no limit and is the default.
• Flow Limit :
Flow Limit specifies the maximum number of running process instances that are spawned before the process starter is suspended ie it enters a FLOW_CONTROLLED state and does not accept new events. This can be used to control the number of process instances running simultaneously and when the protocol generating the event can store the event till it is received, like email servers, JMS, RV etc. 0 specifies no limit and is the default.
• Activation Limit :
Activation limit flag specifies that once a process instance is loaded it must be placed in memory till it completes execution. By default it is enabled.
23.What are the options for configuring storage for process engine’s checkpoint repository ?
The options for configuring storage for process engine’s checkpoint repository are:
• Local File
• Database. Fault tolerant engines can recover from a checkpoint only when database is used.
24.Process engines in a fault tolerant group can be configured as peers or master secondary.How do these differ ?
The options for configuring storage for process engine’s checkpoint repository are:
• – Peer means all of them have the same weight. In this case when one engine fails another one takes over and continues processing till it fails.
• – In master secondary configuration weights are unequal, the secondary starts processing when master fails. But when master recovers, secondary stops and master continues processing.
25.What are the uses of grouping activities ?
Uses of grouping activities are:
• Create a set of activities having a common error transition.
• Repeat group of activities based on a condition.
1. – Iterate over a list.
2. – Repeat until condition true.
3. – Repeat on Error until condition true.
• Group activities into a transaction.
• To create a critical section area that synchronizes process instances.
• A ‘Pick First Group’ allows you to wait for the occurrence of multiple events and proceed along a path following the first event to occur.
26.What is the purpose of a Lock shared configuration resource?
A Lock is specified for a ‘Critical Section’ group when the scope is ‘Multiple’. It can be used to ensure synchronization across process instances belonging to multiple processs definitions or for process instances across engines(Check multi engine flag for lock in this case and the BW engine needs to be configured with database persistence while deployment). If synchronization is for process instances belonging to the same processs definition inside one engine, just specify the scope as ‘Single’.
27.How to control the sequence of execution of process instances created by a process starter ?
Use the sequencing key field in the Misc tab of any process starter. Process instances with the same value for this field are executed in the sequence in which they are started.
28.Can there be two error transitions out of an activity ?
No. There can be only one Error and one Success if no matching condition transition out of each activity.
29.When is a ‘No Action’ group used ?
‘No Action’ group used to have a set of activities having a common error transition

30.What activity can be used to set the value of a ‘User defined process variable’ ?
The ‘Assign’ activity can be used to set the value of a ‘User defined process variable’.

31.Which are the two process variables available to all activities with inputs ?
• $_globalVariables
• $_processContext
32.Which mechanism can be used to pass data between a process instance and a called sub process other than mapping from/to the callee’s input/output ?
This can be accomplished using job shared variables, unless in the call process activity the ‘Spawn’ flag is enabled in which case the called sub process is a new job and hence gets a fresh copy of the job shared variable initialized as per its configuration. A shared variable can overcome this limitation as it’s scope is not limited to one job.

33.What are the three scenarios where BW engine has to be configured with database persistence instead of Local File ?
The three scenarios are:
• Shared Variables across BW engines.
• Locking across groups in multiple BW engines.
• Wait Notify across BW engines.
34.If you want a group to be executed if there is some unhandled error but subject to some max number of iterations which group do you use ?
We can use Repeat on Error until true

35.When is a ‘Generate Error’ activity useful?
When you handle an error inside a called subprocess or group and want to rethrow the error to the caller(happens by default if you dont handle the error in the called process)

36.Which activity is used for detecting duplicate message processing?
CheckPoint activity – Specify the uniqueID for the duplicate key field and engine maintains list of these key fields. When a process come to checkpoint activity with the same value for duplicate key which already exists, it throws a DuplicateException. An error transition can then handle this case.
37.Give an example where graceful migration of service from one machine to another is not possible.
HTTP Receiver. In this case the receiver on new machine starts listening on the same port, but you need to redirect requests from the old machine to the new one.
38.What are the types of adapter services ?
Types of adapter services are :
• Subscriber Service
• Publisher Service
• Request-Response Service
• Request-Response Invocation Service
39.If the business process needs to invoke another web service which resource do you use ?
SOAP request reply activity. If the business process needs to be exposed as SOAP service use SOAP Event Source in conjunction with SOAP Send Reply or SOAP Send Fault.

40.What is the functionality of the Retrieve Resources resource?
It can be used to serve the wsdl file of a SOAP Event Source to a (http) client.
Construct a process like: HTTP Receiver -> Retrieve Resources -> Send HTTP Response

Now the WSDL file for a SOAP service can be retreived using the http request

http://://?wsdl

where ‘path’ is the folder path to the SOAP Event Source process and ‘resourceName’ is the name of the process

Example : http://purch:8877/Purchasing/GetPurchaseOrder?wsdl

41.What is the scope of user defined process variables ?
The scope of user defined process variables is only the process in which it is defined.(Not even inside a sub process that is invoked from this process)
42.What is difference between shared variable and job shared variable ?
• Both of them can be manipulated via the palette resources ‘Get shared variable’ and ‘Set shared variable’.
• A job shared variable is private to one instance of job or in other words each job has a fresh copy. In the case of shared variable the same copy is shared across all job instances. It can even be persisted and can survive BW engine restarts and even shared across multiple BW engines(when deployed using DB persistence).

43.How do wait-notify resources work ?
Basically wait and notify should share a common notification configuration which is just a schema definition for data that will be passed from notifier to waiter. Specific instances of waiter & notifier are corrrelated via a key.
For example: when one process is in wait state for key ‘Order-1’, it waits till another process issues a notification with the same key value.

44.What is the default Axis in XPath ?
Child axis- What this means is that when you select “BOOK” from the current context, it selects a child node with that name, not a sibling with that name. Other axes are parent , self , sibling etc.

45.What are the output formats for XSLT?
• XML
• HTML
• Text

46.What is the Purpose of $_error variable ?
$_error variable is available in the node following the error transition. It captures the error message, error code etc.
47.What are the cases where business process cant proceed correctly subsequent to restart from a checkpoint ?
• Sending HTTP response, confirming an email/jms message etc. This is because the confirmation or sending HTTP response has to done in the same session. When engine crashes these sessions are closed at their socket level. In such cases send response/confirm before checkpoint.

48.Which group do you use to wait for multiple events and proceed with the first to occur ?
A ‘Pick First Group’.

 

 

Top most important android interview questions and answers by Experts:

Here is a list of Top most important android interview questions and answers by Experts.If you want to download android interview questions pdf free ,you can register with RVH techguru. Our experts prepared these android interview questions to accommodate freshers level to most experienced level technical interviews.

If you want to become an expert in android ,Register for android online training here.

 

1) What is Android?
It is an open-sourced operating system that is used primarily on mobile devices, such as cell phones and tablets. It is a Linux kernel-based system that’s been equipped with rich components that allows developers to create and run apps that can perform both basic and advanced functions.
2) What Is the Google Android SDK?
The Google Android SDK is a toolset that developers need in order to write apps on Android enabled devices. It contains a graphical interface that emulates an Android driven handheld environment, allowing them to test and debug their codes.
3) What is the Android Architecture?
Android Architecture is made up of 4 key components:
– Linux Kernel
– Libraries
– Android Framework
– Android Applications
4) What is the importance of XML-based layouts?
The use of XML-based layouts provides a consistent and somewhat standard means of setting GUI definition format. In common practice, layout details are placed in XML files while other items are placed in source files.
5) What are containers?
Containers, as the name itself implies, holds objects and widgets together, depending on which specific items are needed and in what particular arrangement that is wanted. Containers may hold labels, fields, buttons, or even child containers, as examples.
6) What is Orientation?
Orientation, which can be set using setOrientation(), dictates if the LinearLayout is represented as a row or as a column. Values are set as either HORIZONTAL or VERTICAL.
7) What is the importance of Android in the mobile market?
Developers can write and register apps that will specifically run under the Android environment. This means that every mobile device that is Android enabled will be able to support and run these apps. With the growing popularity of Android mobile devices, developers can take advantage of this trend by creating and uploading their apps on the Android Market for distribution to anyone who wants to download it.
8) What do you think are some disadvantages of Android?
Given that Android is an open-source platform, and the fact that different Android operating systems have been released on different mobile devices, there’s no clear cut policy to how applications can adapt with various OS versions and upgrades. One app that runs on this particular version of Android OS may or may not run on another version. Another disadvantage is that since mobile devices such as phones and tabs come in different sizes and forms, it poses a challenge for developers to create apps that can adjust correctly to the right screen size and other varying features and specs.
9) What is adb?
Adb is short for Android Debug Bridge. It allows developers the power to execute remote shell commands. Its basic function is to allow and control communication towards and from the emulator port.
10) What are the four essential states of an activity?
– Active – if the activity is at the foreground
– Paused – if the activity is at the background and still visible
– Stopped – if the activity is not visible and therefore is hidden or obscured by another activity
– Destroyed – when the activity process is killed or completed terminated
11) What is ANR?
ANR is short for Application Not Responding. This is actually a dialog that appears to the user whenever an application have been unresponsive for a long period of time.
12) Which elements can occur only once and must be present?
Among the different elements, the and elements must be present and can occur only once. The rest are optional, and can occur as many times as needed.
13) How are escape characters used as attribute?
Escape characters are preceded by double backslashes. For example, a newline character is created using ‘\n’
14) What is the importance of settings permissions in app development?
Permissions allow certain restrictions to be imposed primarily to protect data and code. Without these, codes could be compromised, resulting to defects in functionality.
15) What is the function of an intent filter?
Because every component needs to indicate which intents they can respond to, intent filters are used to filter out intents that these components are willing to receive. One or more intent filters are possible, depending on the services and activities that is going to make use of it.
16) Enumerate the three key loops when monitoring an activity
– Entire lifetime – activity happens between onCreate and onDestroy
– Visible lifetime – activity happens between onStart and onStop
– Foreground lifetime – activity happens between onResume and onPause
17) When is the onStop() method invoked?
A call to onStop method happens when an activity is no longer visible to the user, either because another activity has taken over or if in front of that activity.
18) Is there a case wherein other qualifiers in multiple resources take precedence over locale?
Yes, there are actually instances wherein some qualifiers can take precedence over locale. There are two known exceptions, which are the MCC (mobile country code) and MNC (mobile network code) qualifiers.
19) What are the different states wherein a process is based?
There are 4 possible states:
– foreground activity
– visible activity
– background activity
– empty process
20) How can the ANR be prevented?
One technique that prevents the Android system from concluding a code that has been responsive for a long period of time is to create a child thread. Within the child thread, most of the actual workings of the codes can be placed, so that the main thread runs with minimal periods of unresponsive times.
21) What role does Dalvik play in Android development?
Dalvik serves as a virtual machine, and it is where every Android application runs. Through Dalvik, a device is able to execute multiple virtual machines efficiently through better memory management.
22) What is the AndroidManifest.xml?
This file is essential in every application. It is declared in the root directory and contains information about the application that the Android system must know before the codes can be executed.
23) What is the proper way of setting up an Android-powered device for app development?
The following are steps to be followed prior to actual application development in an Android-powered device:
-Declare your application as “debuggable” in your Android Manifest.
-Turn on “USB Debugging” on your device.
-Set up your system to detect your device.
24) Enumerate the steps in creating a bounded service through AIDL.
1. create the .aidl file, which defines the programming interface
2. implement the interface, which involves extending the inner abstract Stub class as well as implanting its methods.
3. expose the interface, which involves implementing the service to the clients.
25) What is the importance of Default Resources?
When default resources, which contain default strings and files, are not present, an error will occur and the app will not run. Resources are placed in specially named subdirectories under the project res/ directory.
26) When dealing with multiple resources, which one takes precedence?
Assuming that all of these multiple resources are able to match the configuration of a device, the ‘locale’ qualifier almost always takes the highest precedence over the others.
27) When does ANR occur?
The ANR dialog is displayed to the user based on two possible conditions. One is when there is no response to an input event within 5 seconds, and the other is when a broadcast receiver is not done executing within 10 seconds.
28) What is AIDL?
AIDL, or Android Interface Definition Language, handles the interface requirements between a client and a service so both can communicate at the same level through interprocess communication or IPC. This process involves breaking down objects into primitives that Android can understand. This part is required simply because a process cannot access the memory of the other process.

29) What data types are supported by AIDL?
AIDL has support for the following data types:
-string
-charSequence
-List
-Map
-all native Java data types like int,long, char and Boolean
30) What is a Fragment?
A fragment is a part or portion of an activity. It is modular in a sense that you can move around or combine with other fragments in a single activity. Fragments are also reusable.
31) What is a visible activity?
A visible activity is one that sits behind a foreground dialog. It is actually visible to the user, but not necessarily being in the foreground itself.
32) When is the best time to kill a foreground activity?
The foreground activity, being the most important among the other states, is only killed or terminated as a last resort, especially if it is already consuming too much memory. When a memory paging state has been reach by a foreground activity, then it is killed so that the user interface can retain its responsiveness to the user.
33) Is it possible to use or add a fragment without using a user interface?
Yes, it is possible to do that, such as when you want to create a background behavior for a particular activity. You can do this by using add(Fragment,string) method to add a fragment from the activity.
34) How do you remove icons and widgets from the main screen of the Android device?
To remove an icon or shortcut, press and hold that icon. You then drag it downwards to the lower part of the screen where a remove button appears.
35) What are the core components under the Android application architecture?
There are 5 key components under the Android application architecture:
– services
– intent
– resource externalization
– notifications
– content providers
36) What composes a typical Android application project?
A project under Android development, upon compilation, becomes an .apk file. This apk file format is actually made up of the AndroidManifest.xml file, application code, resource files, and other related files.
37) What is a Sticky Intent?
A Sticky Intent is a broadcast from sendStickyBroadcast() method such that the intent floats around even after the broadcast, allowing others to collect data from it.
38) Do all mobile phones support the latest Android operating system?
Some Android-powered phone allows you to upgrade to the higher Android operating system version. However, not all upgrades would allow you to get the latest version. It depends largely on the capability and specs of the phone, whether it can support the newer features available under the latest Android version.
39) What is portable wi-fi hotspot?
Portable Wi-Fi Hotspot allows you to share your mobile internet connection to other wireless device. For example, using your Android-powered phone as a Wi-Fi Hotspot, you can use your laptop to connect to the Internet using that access point.
40) What is an action?
In Android development, an action is what the intent sender wants to do or expected to get as a response. Most application functionality is based on the intended action.
41) What is the difference between a regular bitmap and a nine-patch image?
In general, a Nine-patch image allows resizing that can be used as background or other image size requirements for the target device. The Nine-patch refers to the way you can resize the image: 4 corners that are unscaled, 4 edges that are scaled in 1 axis, and the middle one that can be scaled into both axes.
42) What language is supported by Android for application development?
The main language supported is Java programming language. Java is the most popular language for app development, which makes it ideal even for new Android developers to quickly learn to create and deploy applications in the Android environment.
43) What is meaning of Android Word?
it means a robot with a human appearance.

44) What is Android?
an open-source operating system used for smartphones and tablet computers.

45) Inventors of android ?
Andy Rubin, Rich Miner, Nick Sears5. Features of Android OS?
Most of us are aware of features like
Live wallpaper
Camera
Messaging
Bluetooth
WIFI
Web Browsing
Music
Alarm etc. etc….

46) Advance Features of Android OS?
Google now (voice assistant)
NFC (Near Field Communication)
Unlock your phone by your face
Use your phone with joystick to enjoy gaming experience
Connect your phone with LED TV via MHL or micro HDMI cable
Screen Capture
Multitasking Future (Task Switcher)
Data Usages (Check and also set limit from device)

47) Tools Required for Developing Android Apps?
JDK
Eclipse + ADT plugin
SDK Tools.
48) ADT stand for?
Android Developer Tools

49) SDK stand for ?
Software Development Kit

50) Advantages of android?
Open-source
Platform-independent
Supports various technologies (having number of native application like: camera, bluetooth, wifi, speech, EDGE)

51) Describe the Android Framework.
The Android Framework is an important aspect of the Android Architecture. Here you can find all the classes and methods that developers would need in order to write applications on the Android environment.
52) What is AAPT?
AAPT is short for Android Asset Packaging Tool. This tool provides developers with the ability to deal with zip-compatible archives, which includes creating, extracting as well as viewing its contents.
53) What is the importance of having an emulator within the Android environment?
The emulator lets developers “play” around an interface that acts as if it were an actual mobile device. They can write and test codes, and even debug. Emulators are a safe place for testing codes especially if it is in the early design phase.
54) What is the use of an activityCreator?
An activityCreator is the first step towards the creation of a new Android project. It is made up of a shell script that will be used to create new file system structure necessary for writing codes within the Android IDE.
55) Describe Activities.
Activities are what you refer to as the window to a user interface. Just as you create windows in order to display output or to ask for an input in the form of dialog boxes, activities play the same role, though it may not always be in the form of a user interface.
56) What are Intents?
Intents displays notification messages to the user from within the Android enabled device. It can be used to alert the user of a particular state that occurred. Users can be made to respond to intents.
57) Differentiate Activities from Services.
Activities can be closed, or terminated anytime the user wishes. On the other hand, services are designed to run behind the scenes, and can act independently. Most services run continuously, regardless of whether there are certain or no activities being executed.
58) What items are important in every Android project?
These are the essential items that are present each time an Android project is created:
– AndroidManifest.xml
– build.xml
– bin/
– src/
– res/
– assets/

 

 

Top most important pl sql interview questions and answers by Experts:

Here is a list of Top most important pl sql interview questions and answers by Experts.If you want to download pl sql interview questions pdf free ,you can register with RVH techguru. Our experts prepared these pl sql interview questions to accommodate freshers level to most experienced level technical interviews.

If you want to become an expert in pl sql ,Register for pl sql online training here.

 

1.What special operators does Oracle provide for dealing with NULLs?

NVL – Converts a NULL to another specified value, as in:

my_var := NVL (your_var, ‘Hello’);

IS NULL and IS NOT NULL

You can use this syntax to check specificaly to see if a variable’s value is NULL or NOT NULL.

2.Explain three different rules that apply to NULLs when doing comparisons?

1. For all operators except for concatenation (||), if a value in an expression is a NULL, that expression evaluates to NULL

2. NULL is never equal or not equal to another value

3. NULL is never TRUE or FALSE

3.What command would you use to encrypt a PL/SQL application?

WRAP

4.Explain the difference between a FUNCTION, PROCEDURE and PACKAGE.

A function has a return type in its specification and must return a value specified in that type. A procedure does not have a return type in its specification and should not return any value, but it can have a return statement that simply stops its execution and returns to the caller.

5.What steps are included in the compilation process of a PL/SQL block?

The compilation process includes syntax checking, binding, and p-code generation. Syntax checking involves checking PL/SQL code for compilation errors. After syntax errors have been corrected, a storage address is assigned to the variables that are used to hold data for Oracle. This process is called binding. Next, p-code is generated for the PL/SQL block. P-code is a list of instructions to the PL/SQL engine. For named blocks, p-code is stored in the database, and it is used the next time the program is executed.

6.How does a syntax error differ from a runtime error?

A syntax error can be detected by the PL/SQL compiler. A runtime error occurs while the program is running and cannot be detected by the PL/SQL compiler.

A misspelled keyword is an example of a syntax error. For example, this script:

BEIN
DBMS_OUTPUT.PUT_LINE (‘This is a test’);
END;

contains a syntax error. Try to find it.

A SELECT INTO statement returning no rows is an example of a runtime error. This error can be handled with the help of the exception-handling section of the PL/SQL block.

Define Commit, Rollback and Savepoint.

When a COMMIT statement is issued to the database, the transaction has ended, and the following results are true:

. All work done by the transaction becomes permanent.

. Other users can see changes in data made by the transaction.

. Any locks acquired by the transaction are released.

When a ROLLBACK statement is issued to the database, the transaction has ended, and the following results are true:

. All work done by the transaction is undone, as if it hadn’t been issued.

. Any locks acquired by the transaction are released.

The ROLLBACK statement undoes all the work done by the user in a specific transaction. With the SAVEPOINT command, however, only part of the transaction can be undone.

7.Explain Implicit and Explicit cursors

Oracle automatically declares an implicit cursor every time a SQL statement is executed. The user is unaware of this and cannot control or process the information in an implicit cursor.

The program defines an explicit cursor for any query that returns more than one row of data. This means that the programmer has declared the cursor within the PL/SQL code block. This declaration allows the application to sequentially process each row of data as the cursor returns it.

8.How an Implicit cursor works?

1. Any given PL/SQL block issues an implicit cursor whenever a SQL statement is executed, as long as an explicit cursor does not exist for that SQL statement.
2. A cursor is automatically associated with every DML (data manipulation) statement (UPDATE, DELETE, INSERT).
3. All UPDATE and DELETE statements have cursors that identify the set of rows that will be affected by the operation.
4. An INSERT statement needs a place to receive the data that is to be inserted into the database; the implicit cursor fulfills this need.
5. The most recently opened cursor is called the SQL cursor.

9.How an Explicit cursor works?

The process of working with an explicit cursor consists of the following steps:

1. Declaring the cursor. This initializes the cursor into memory.

2. Opening the cursor. The declared cursor is opened, and memory is allotted.

3. Fetching the cursor. The declared and opened cursor can now retrieve data.

4. Closing the cursor. The declared, opened, and fetched cursor must be closed to release the memory allocation.

10.What are PL/SQL Cursor Exceptions?

Cursor_Already_Open, Invalid_Cursor

11.What is the maximum number of triggers, can apply to a single table?

12 triggers.

12.What is a mutating table error and how can you get around it?

This happens with triggers. It occurs because the trigger is trying to update a row it is currently using. The usual fix involves either use of views or temporary tables so the database is selecting from one while updating the other.

13.What packages (if any) has Oracle provided for use by developers?

Oracle provides the DBMS_ series of packages. There are many which developers should be aware of such as DBMS_SQL, DBMS_PIPE, DBMS_TRANSACTION, DBMS_LOCK, DBMS_ALERT, DBMS_OUTPUT, DBMS_JOB, DBMS_UTILITY, DBMS_DDL, UTL_FILE. If they can mention a few of these and describe how they used them, even better. If they include the SQL routines provided by Oracle, great, but not really what was asked.

Describe the use of PL/SQL tables

PL/SQL tables are scalar arrays that can be referenced by a binary integer. They can be used to hold values for use in later queries or calculations. In Oracle 8 they will be able to be of the %ROWTYPE designation, or RECORD.

14.When is a declare statement needed?

The DECLARE statement is used in PL/SQL anonymous blocks such as with stand alone, non-stored PL/SQL procedures. It must come first in a PL/SQL stand alone file if it is used.

In what order should a open/fetch/loop set of commands in a PL/SQL block be implemented if you use the %NOTFOUND cursor variable in the exit when statement? Why?

OPEN then FETCH then LOOP followed by the exit when. If not specified in this order will result in the final return being done twice because of the way the %NOTFOUND is handled by PL/SQL.

15.What are SQLCODE and SQLERRM and why are they important for PL/SQL developers?

SQLCODE returns the value of the error number for the last error encountered. The SQLERRM returns the actual error message for the last error encountered. They can be used in exception handling to report, or, store in an error log table, the error that occurred in the code. These are especially useful for the WHEN OTHERS exception.

16.How can you find within a PL/SQL block, if a cursor is open?

Use the %ISOPEN cursor status variable.

17.How can you generate debugging output from PL/SQL?

Use the DBMS_OUTPUT package. Another possible method is to just use the SHOW ERROR command, but this only shows errors. The DBMS_OUTPUT package can be used to show intermediate results from loops and the status of variables as the procedure is executed. The new package UTL_FILE can also be used.

18.What are the types of triggers?

There are 12 types of triggers in PL/SQL that consist of combinations of the BEFORE, AFTER, ROW, TABLE, INSERT, UPDATE, DELETE and ALL key words:
BEFORE ALL ROW INSERT
AFTER ALL ROW INSERT
BEFORE INSERT
AFTER INSERT etc.

19.How can I define a two-dimensional array of numbers in PL/SQL?

Although PL/SQL does not natively support the declaration and manipulation of multidimensional arrays, you can emulate these structures using nested collection definitions, which were first supported in Oracle9i Database Release 1.

Here is a brief example to get you started and introduce you to some of the challenges you may encounter as you use collections in this way.

First, create a collection of associative arrays.

CREATE OR REPLACE PACKAGE twodim_aa
IS
TYPE data_t IS TABLE OF NUMBER
INDEX BY PLS_INTEGER;

TYPE array_t IS TABLE OF data_t
INDEX BY PLS_INTEGER;
END twodim_aa;
/

The first, inner collection—data_t—contains the data for each cell in the two-dimensional array. Each row in the outer collection—array_t—contains a collection of the first type.

Now declare a variable based on that outer collection type —array_t—, which will serve as a two-dimensional array. In the following script, I declare such a collection—

DECLARE
l_2d_grid twodim_aa.array_t;

—and then assign values to three cells: (1,1), (1,2), and (200,206). Notice that the syntax is different from that used in traditional array cell specification, namely: (1)(1), (1)(2), and (200)(206). Also, since I am using associative arrays to define my two-dimensional array, I do not have to specify a size for this two-dimensional array.

DECLARE
l_2d_grid twodim_aa.array_t;
BEGIN
l_2d_grid (1) (1) := 100;
l_2d_grid (1) (2) := 120;
l_2d_grid (200) (206) := 200;

IF l_2d_grid (1)(2)

20.What is PL/SQL?
PL/SQL stands for procedural language extension to SQL. It supports procedural features of programming language and SQL both. It was developed by Oracle Corporation in early of 90’s to enhance the capabilities of SQL.

21. What is PL/SQL table? Why it is used?
Objects of type tables are called PL/SQL tables that are modeled as database table. We can also say that PL/SQL tables are a way to providing arrays. Arrays are like temporary tables in memory that are processed very quickly. PL/SQL tables are used to move bulk data. They simplifies moving collections of data.

22. What are the datatypes available in PL/SQL?
There are two types of datatypes in PL/SQL:
1. Scalar datatypes Example are NUMBER, VARCHAR2, DATE, CHAR, LONG, BOOLEAN etc.
2. Composite datatypes Example are RECORD, TABLE etc
23. What is the basic structure of PL/SQL?
PL/SQL uses BLOCK structure as its basic structure. Each PL/SQL program consists of SQL and PL/SQL statement which form a PL/SQL block.
PL/SQL block contains 3 sections.
1. The Declaration Section (optional)
2. The Execution Section (mandatory)
3. The Exception handling Section (optional)

24. What is the difference between FUNCTION, PROCEDURE AND PACKAGE in PL/SQL?
Function: The main purpose of a PL/SQL function is generally to compute and return a single value. A function has a return type in its specification and must return a value specified in that type.
Procedure: A procedure does not have a return type and should not return any value but it can have a return statement that simply stops its execution and returns to the caller. A procedure is used to return multiple values otherwise it is generally similar to a function.
Package: A package is schema object which groups logically related PL/SQL types , items and subprograms. You can also say that it is a group of functions, procedure, variables and record type statement. It provides modularity, due to this facility it aids application development. It is used to hide information from unauthorized users.

25.What is exception? What are the types of exceptions?
Exception is an error handling part of PL/SQL. There are two type of exceptions: pre_defined exception and user_defined exception.
26.How exception is different from error?
Whenever an Error occurs Exception arises. Error is a bug whereas exception is a warning or error condition.

27.What is the main reason behind using an index?
Faster access of data blocks in the table.

28. What are PL/SQL exceptions? Tell me any three.
1. Too_many_rows
2. No_Data_Found
3. Value_error
4. Zero_error etc.

29. What is the maximum number of triggers, you can apply on a single table?
12 triggers.

30.How many types of triggers exist in PL/SQL?
There are 12 types of triggers in PL/SQL that contains the combination of BEFORE, AFTER, ROW, TABLE, INSERT, UPDATE, DELETE and ALL keywords.
• BEFORE ALL ROW INSERT
• AFTER ALL ROW INSERT
• BEFORE INSERT
• AFTER INSERT etc.

31. What is stored Procedure?
A stored procedure is a sequence of statement or a named PL/SQL block which performs one or more specific functions. It is similar to a procedure in other programming languages. It is stored in the database and can be repeatedly executed. It is stored as schema object. It can be nested, invoked and parameterized.

32.How to execute a stored procedure?
There are two way to execute a stored procedure.
From the SQL prompt, write EXECUTE or EXEC followed by procedure_name.
1. EXECUTE or [EXEC] procedure_name;
Simply use the procedure name
1. procedure_name;

33. What are the advantages of stored procedure?
Modularity, extensibility, reusability, Maintainability and one time compilation.

34. What are the cursor attributes used in PL/SQL?
%ISOPEN: it checks whether the cursor is open or not.
%ROWCOUNT: returns the number of rows affected by DML operations: INSERT,DELETE,UPDATE,SELECT.
%FOUND: it checks whether cursor has fetched any row. If yes – TRUE.
%NOTFOUND: it checks whether cursor has fetched any row. If no – TRUE.

35. What is consistency?
Consistency simply means that each user sees the consistent view of the data.
Consider an example: there are two users A and B. A transfers money to B’s account. Here the changes are updated in A’s account (debit) but until it will be updated to B’s account (credit), till then other users can’t see the debit of A’s account. After the debit of A and credit of B, one can see the updates. That?s consistency.

36. What is cursor and why it is required?
A cursor is a temporary work area created in a system memory when an SQL statement is executed.
A cursor contains information on a select statement and the row of data accessed by it. This temporary work area stores the data retrieved from the database and manipulate this data. A cursor can hold more than one row, but can process only one row at a time. Cursor are required to process rows individually for queries.

37. How many types of cursors are available in PL/SQL?
There are two types of cursors in PL/SQL.
1. Implicit cursor, and
2. explicit cursor

38.What is a cursor? Define explicit and implicit cursor.
The oracle engine opens a work area for each SQL’s operations for its internal processing in order to execute SQL statements. This area is private to SQL’s operations and is called as a cursor.

Implicit cursor – If the oracle engine has opened a cursor for its internal processing, then it is implicit cursor.

Explicit cursor – It is also known as user defined cursor. When a user opens a cursor for processing data, the cursor is explicit cursor.
39.Explain about the cursor attributes.
Each cursor or cursor variable has four attributes:

%FOUND, %ISOPEN, %NOTFOUND and %ROWCOUNT

When appended to the cursor, these attributes return useful information about the execution of a data manipulation statement.
40.What are the restrictions of using cursor variables?
-PL/SQL tables cannot store cursor variables.
-Remote subprogram cannot return the value of a cursor variable.
41.What is a trigger in PLSQL?
A trigger is a PLSQL block that is executed whenever an event occurs. It fires implicitly whenever the triggering event happens, a trigger never accepts argument. A trigger cannot be used for a SELECT statement.
42.What are the triggers supported in oracle?
-DML triggers
-Instead of triggers
-DDL triggers
-Database event triggers

DML triggers

It is defined on a table and fires in response to an event like

– When a row is inserted to a table
– When a row is updated
– When a row is deleted

Instead of trigger

This trigger is created on views. You can either use Insert or Update or Delete or all three actions.
What are triggering attributes?
Triggering attributes are used to catch event when you want to identify or to perform certain actions.

They are as follows:

Inserting
Updating
Deleting
43.What is the difference between a function and a procedure in oracle?
A function always returns a value back to the calling block.
44.What are packages?
A package is an encapsulated collection of related schema objects. A package is compiled and then stored in the database’s data dictionary as a schema objects. These objects can be procedure, functions, variables, constants, cursors and exceptions.
45.Explain the difference between GRANT and REVOKE command.
GRANT command is used to allow a user to perform certain activities on the database. The REVOKE command disallows the user from performing certain activities.
Explain the difference between ROLLBACK and COMMIT commands.
The COMMIT command is used to save the modifications done to the database values by the DML commands.

ROLLBACK command is used to undo the changes made by the DML commands. This ensures the values that existed prior to the changes can be achieved.
46.Define Row level trigger.
Row level trigger is fired each time a row is affected by DML statements like Insert, Update and Delete. When no rows affected, the trigger is not executed at all.
47.Define Statement level triggers.
It is fired when statement affects rows in a table but the processing required is completely independent of the number of rows affected.
48.Define Joins and its types.
A join is a query that extracts corresponding rows from two or more tables, views or snapshots.

Types:

Equi-joins
Non-equi joins
Self joins
Outer joins

Equi-join – information from two or more tables are retrieved by using equality conditions.

Self joins – Self join is a join that relates to itself.

Outer joins – Outer join fetch the rows from two tables which matches the join condition and the rows which don’t match the join condition.

 

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1) What is Python? What are the benefits of using Python?
Python is a programming language with objects, modules, threads, exceptions and automatic memory management. The benefits of pythons are that it is simple and easy, portable, extensible, build-in data structure and it is an open source.
2) What is PEP 8?
PEP 8 is a coding convention, a set of recommendation, about how to write your Python code more readable.
3) What is pickling and unpickling?
Pickle module accepts any Python object and converts it into a string representation and dumps it into a file by using dump function, this process is called pickling. While the process of retrieving original Python objects from the stored string representation is called unpickling.
4) How Python is interpreted?
Python language is an interpreted language. Python program runs directly from the source code. It converts the source code that is written by the programmer into an intermediate language, which is again translated into machine language that has to be executed.
5) How memory is managed in Python?
• Python memory is managed by Python private heap space. All Python objects and data structures are located in a private heap. The programmer does not have an access to this private heap and interpreter takes care of this Python private heap.
• The allocation of Python heap space for Python objects is done by Python memory manager. The core API gives access to some tools for the programmer to code.
• Python also have an inbuilt garbage collector, which recycle all the unused memory and frees the memory and makes it available to the heap space.
6) What are the tools that help to find bugs or perform static analysis?
PyChecker is a static analysis tool that detects the bugs in Python source code and warns about the style and complexity of the bug. Pylint is another tool that verifies whether the module meets the coding standard.
7) What are Python decorators?
A Python decorator is a specific change that we make in Python syntax to alter functions easily.
8) What is the difference between list and tuple?
The difference between list and tuple is that list is mutable while tuple is not. Tuple can be hashed for e.g as a key for dictionaries.
9) How are arguments passed by value or by reference?
Everything in Python is an object and all variables hold references to the objects. The references values are according to the functions; as a result you cannot change the value of the references. However, you can change the objects if it is mutable.
10) What is Dict and List comprehensions are?
They are syntax constructions to ease the creation of a Dictionary or List based on existing iterable.
11) What are the built-in type does python provides?
There are mutable and Immutable types of Pythons built in types Mutable built-in types
• List
• Sets
• Dictionaries
Immutable built-in types
• Strings
• Tuples
• Numbers
12) What is namespace in Python?
In Python, every name introduced has a place where it lives and can be hooked for. This is known as namespace. It is like a box where a variable name is mapped to the object placed. Whenever the variable is searched out, this box will be searched, to get corresponding object.
13) What is lambda in Python?
It is a single expression anonymous function often used as inline function.
14) Why lambda forms in python does not have statements?
A lambda form in python does not have statements as it is used to make new function object and then return them at runtime.
15) What is pass in Python?
Pass means, no-operation Python statement, or in other words it is a place holder in compound statement, where there should be a blank left and nothing has to be written there.
16) In Python what are iterators?
In Python, iterators are used to iterate a group of elements, containers like list.
17) What is unittest in Python?
A unit testing framework in Python is known as unittest. It supports sharing of setups, automation testing, shutdown code for tests, aggregation of tests into collections etc.
18) In Python what is slicing?
A mechanism to select a range of items from sequence types like list, tuple, strings etc. is known as slicing.
19) What are generators in Python?
The way of implementing iterators are known as generators. It is a normal function except that it yields expression in the function.
20) What is docstring in Python?
A Python documentation string is known as docstring, it is a way of documenting Python functions, modules and classes. 
21) How can you copy an object in Python?
To copy an object in Python, you can try copy.copy () or copy.deepcopy() for the general case. You cannot copy all objects but most of them.
22) What is negative index in Python?
Python sequences can be index in positive and negative numbers. For positive index, 0 is the first index, 1 is the second index and so forth. For negative index, (-1) is the last index and (-2) is the second last index and so forth.
23) How you can convert a number to a string?
In order to convert a number into a string, use the inbuilt function str(). If you want a octal or hexadecimal representation, use the inbuilt function oct() or hex().
24) What is the difference between Xrange and range?
Xrange returns the xrange object while range returns the list, and uses the same memory and no matter what the range size is.
25) What is module and package in Python?
In Python, module is the way to structure program. Each Python program file is a module, which imports other modules like objects and attributes.
The folder of Python program is a package of modules. A package can have modules or subfolders.
26) What is Python?
Python is an object oriented and open-source programming language, which supports structured and functional built-in data structures. With a placid and easy-to -understand syntax, Python allows code reuse and modularity of programs. The built-in DS in Python makes it a wonderful option for Rapid Application Development (RAD). The coding language also encourages faster editing, testing and debugging with no compilation steps.
27) What are the standard data types supported by Python?
It supports six data types:
1. Number : object stored as numeric value
2. String : object stored as string
3. Tuple : data stored in the form of sequence of immutable objects
4. Dictionary (dicts): associates one thing to another irrespective of the type of data, most useful container (called hashes in C and Java)
5. List : data stored in the form of a list sequence
6. Set (frozenset): unordered collection of distinct objects
28) Explain built-in sequence types in Python Programming?
It provides two built in sequence types-
1. Mutable Type : objects whose value can be changed after creation, example: sets, items in the list, dictionary
2. Immutable type : objects whose value cannot be changed once created, example: number, Boolean, tuple, string
29) Explain the use of iterator in Python?
Python coding uses Iterator to implement the iterator protocol, which enables traversing trough containers and group of elements like list.The two important methods include _iter_() returning the iterator object and next() method for traversal.
30) Define Python slicing ?
The process of extracting a range of elements from lists, arrays, tuples and custom Python data structures as well. It works on a general start and stop method: slice (start, stop, increment)
31) How can you compare two lists in Python?
We can simply perform it using compare function – cmp(rvhtechlist1, rvhtechlist2)
def cmp(rvhtechlist1, rvhtechlist2):
for val in rvhtechlist1:
if val in rvhtechlist2:
returnTrue
returnFalse
32) What is the use of // operator?
‘//’ is a Floor Divisionoperator, which divides two operands with the result as quotient showing only digits before decimal point.For instance, 6//3 = 2 and 6.0//3.0 = 2.0
33) Define docstring in Python with example.
A string literal occurring as the first statement (like a comment) in any module, class, function or method is referred as docstring in Python. This kind of string becomes the _doc_ special attribute of the object and provides an easy way to document a particular code segment. Most modules do contain docstrings and thus, the functions and classes extracted from the module also consist of docstrings.
34) What function randomizes the items of a list in place?
Using shuffle() function
For instance:
import randomize
lst = [2, 18, 8, 4];
randomize.shuffle(lst)
print “Shuffled list : “, lst
random.shuffle(list)
print “Reshuffled list : “, list
35) List five benefits of using Python?
1. Having the built-in data types, Python saves programmer’s time and effort from declaring variables. It has a powerful dict ionary and polymorphic list for automatic declaration. It also ensures better code reusability
2. Highly accessible and easy-to-learn for beginners and a strong ‘glue’ for advanced Professionals consisting fo several high-level modules and operations not performed by other programming languages.
3. Allows easy readability due to use of square brackets for most functions and indexes
4. Python requires no explicit memory management as the interpreter itself allocates the memory to new variables and free them automatically.
5. Python comprises a huge standard library for most Internet platforms like Email, HTML, FTP and other WWW platforms.
36) What are the disadvantages of using Python?
1. Python is slow as compared to other programming languages. Although, this slow pace doesn’t matter much, at times, we need other language to handle performance-critical situations.
2. It is ineffective on mobile platforms; fewer mobile applications are developed using python. The main reason behind its instability on smartphones is Python’s weakest security. There are no good secure cases available for Python until now
3. Due to dynamic typing, Programmers face design restrictions while using the language. The code needs more and more testing before putting it into action since the errors pop up only during runtime.
4. Unlike JavaScript, Python’s features like concurrency and parallelism are not developed for elegant use.
37) Explain the use of split function?
The split() function in Python breaks a string into shorter strings using the defined separator. It renders a list of all words present in the string.
>>> y= ‘true,false,none’
>>> y.split(‘,’)
Result: (‘true’, ‘false’, ‘none’)
What is the use of generators in Python?
Generators are primarily used to return multiple items but one after the other. They are used for iteration in Python and for calculating large result sets. The generator function halts until the next time request is placed.
One of the best uses of generators in Python coding is implementing callback operation with reduced effort and time. They replace callback with iteration. Through the generator approach, programmers are saved from writing a separate callback function and pass it to work-function as it can applying ‘for’ loop around the generator.
38) How to create a multidimensional list in Python?
As the name suggests, a multidimensional list is the concept of a list holding another list, applying to many such lists. It can be one easily done by creating single dimensional list and filling each element with a newly created list.
39) What is lambda?
lambda is a powerful concept used in conjunction with other functions like filter(), map(), reduce(). The major use of lambda construct is
to create anonymous functions during runtime, which can be used where they are created. Such functions are actually known as throw-away functions in Python. The general syntax is lambda argument_list:expression.
For instance:
>>> def rvhtech1 = lambda i, n : i+n
>>> rvhtech(2,2)
4
Using filter()
>> rvhtech= [1, 6, 11, 21, 29, 18, 24]
>> print filter (lambda x: x%3 = = 0, rvhtech)
[6, 21, 18, 24]
40) Define Pass in Python?
The pass statement in Python is equivalent to a null operation and a placeholder, wherein nothing takes place after its execution. It is mostly used at places where you can let your code go even if it isn’t written yet.
If you would set out a pass after the code, it won’t run. The syntax is pass
41) How to perform Unit Testing in Python?
Referred to as PyUnit, the python Unit testing framework-unittest supports automated testing, seggregating test into collections, shutdown testing code and testing independence from reporting framework. The unittest module makes use of TestCase class for holding and preparing test routines and clearing them after the successful execution.
42) Define Python tools for finding bugs and performing static analysis?
. PyChecker is an excellent bug finder tool in Python, which performs static analysis unlike C/C++ and Java. It also notifies the programmers about the complexity and style of the code. In addition, there is another tool, PyLint for checking the coding standards including the code line length, variable names and whether the interfaces declared are fully executed or not.
43) How to convert a string into list?
Using the function list(string). For instance:
>>> list(‘rvhtech’) in your lines of code will return
[‘i’, ‘n’, ‘t’, ‘e’, ‘l’, ‘l’, ‘i’, ‘p’, ‘a’, ‘a’, ‘t’]
In Python, strings behave like list in various ways. Like, you can access individual characters of a string
>> > y = “rvhtech”
>>> s[2]
‘t’
44) What OS do Python support?
Linux, Windows, Mac OS X, IRIX, Compaq, Solaris

45) Define docstring in Python.
A string literal occurring as the first statement (like a comment) in any module, class, function or method is referred as docstring in Python. This kind of string becomes the _doc_ special attribute of the object and provides an easy way to document a particular code segment. Most modules do contain docstrings and thus, the functions and classes extracted from the module also consist of docstrings.
46) Name the optional clauses used in a ‘try-except’ statement in Python?
While Python exception handling is a bit different from Java, the former provides an option of using a try-except clause where the programmer receives a detailed error message without termination the program. Sometimes, along with the problem, this try-except statement offers a solution to deal with the error.
The language also provides try-except-finally and try-except-else blocks.
47)  How to use PYTHOPATH?
PYTHONPATH is the environment variable consisting of directories. $PYTHONPATH is used for searching the actual list of folders for libraries.
48) Define ‘self’ in Python?
self is a reference to the current instance of the class. It is just like ‘this’ in JavaScript. While we create an instance of a class, that instance has its data, which internally passes a reference to it‘self’

49) Define CGI?
Common Gateway Interface support in Python is an external gateway to interact with HTTP server and other information servers. It consists of a series of standards and instructions defining the exchange of information between a custom script and web server. The HTTP server puts all important and useful information concerning the request in the script environment and then run the script and sends it back in the form of output to the client.
50) What is PYTHONSTARTUP and how is it used?
PYTHONSTARTUP is yet another environment variable to test the Python file in the interpreter using interactive mode. The script file is executed even before the first prompt is seen. Additionally, it also allows reloading of the same script file after being modified in the external editor.
51) What is the return value of trunc() in Python?
truc() returns integer value. Uses the _trunc_ method
>>> import rvhtech
rvhtech.trunc(4.34)
4

52) How to convert a string to an object in Python?
To convert string into object, Python provides a function eval(string). It allows the Python code to run in itself
53) Is there any function to change case of all letters in the string?
Yes, Python supports a function swapcase(), which swaps the current letter case of the string. This method returns a copy of the string with the string case swapped.
54) What is pickling and unpickling in Python?
The process of Pickling relates to the Pickle module. Pickle is a general module that acquires a python object and converts it into string. It further dumps that string object into a file by using dump () function.
Pickle comprises two methods:
Dump (): dumps an object to a file object
and Load (): loads an object from a file object
Unpickling is the reacquiring process to perform retrieval of the original Python object from the stored string for reuse.
55) What are the rules for local and global variables in Python?
Local and global variables – If a variable is defined outside function then it is implicitly global. If variable is assigned new value inside the function means it is local…
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